I. Field of the Invention
The field of this invention is that of contrast agents for magnetic resonance imaging (MRI). More specifically, this invention relates to a method and reagent for use in magnetic resonance imaging of abscesses.
II. Description of the Related Art
Magnetic resonance imaging (MRI) is known as an imaging modality for diagnosing various conditions in a patient. In order to specifically image a particular tissue in the body, it is necessary to direct a contrast agent having paramagnetic or super-paramagnetic properties to the tissue to be imaged. It is known as disclosed in U.S. Pat. No. 4,729,892 to use cross-linked hydrogel materials as contrast agents for imaging gastrointestinal tract. It is also known as disclosed in U.S. Pat. No. 4,669,481 to Eisenberg et al to label red blood cells with chromium for imaging the liver or spleen. It is also known as disclosed in U.S. Pat. No. 4,669,481 to Eisenberg et al. to use metal chelates, such as Gd-DTPA and nitroxide stable radicals (NSFRs) as contrast agents however these agents are of limited use because of target specificity, toxicity and relatively short duration signal.
Heretofore, the ability to determine the nature of abscess in a patient has been accomplished only by computerized tomography and ultra sound. These modalities cannot distinguish an abscess from a neoplastic mass. Because of the non-invasive characteristics of magnetic resonance imaging, it would be useful to image abscesses by magnetic resonance imaging. Therefore, it would be advantageous to provide a contrast agent which would target abscesses and provide sufficient contrast to distinguish abcess from neoplastic mass.